Germicide

a germ killer. Current discussions divide germicides into three classes--mechanical, physical, and chemical. Germs are so minute that no process of grinding or pounding can be effective. Prolonged shaking prevents multiplication in many cases, and even kills germs. Of physical agencies, heat, light, cold, and electricity are the most important. Heat is the most effective; electricity the least so. No germ can withstand a high degree of heat. Nearly all germs are killed by the temperature of boiling water. Speaking in a general way, bacteria can stand more heat than animal germs. Freezing kills some germs; others live dormant in ice. Some live even in liquid air. There is no practical method of killing bacteria by freezing. Prolonged sunlight is nature's great germicide. Some forms of disease seem to yield to the influence of red light, X-rays, radium, etc., but the nature of their action is not understood, nor are the results certain. Strong, white sunlight is the greatest of physical germ destroyers. Electrical currents cannot be depended upon to kill germs. Polluted water, through which a powerful current has been passed, is found to be full of germs. Of chemical germicides, carbolic acid is without a superior. Other anti-bacterial agents are ammonia, chloride of lime, creosote, formaldehyde, alcohol, hydrogen peroxide, mercury, and iodine. Sulphur is less in favor than formerly. A number of oils, as of peppermint, pennyroyal, turpentine, and mustard are effective. Quinine and its ally, salicylic acid, are the standard remedies for malarial germs. Fortunately the blood itself, or rather the serum of the blood, is one of the most efficient germicides in nature.